The world's lightest material is carbon aerogel which has a mass of only 0.16 milligram and it is even lighter than aerographite.
Answer: (i) F = 2
(ii) F = 3
(iii) F = 2
Explanation:
We would be applying the famous Gibbs Phase Rule to explaining this problem;
By applying the formula;
F+P = C +2
Where P = this represent the phase
F = this is called the degree of freedom
C = this represent the component in the system
Ok let us begin;
(i). from this we can see that there are 2 components i.e. (water + ethanol) and the phase in question is a vapor phase + liquid phase.
So from the formula;
F = C-P+2
F = 2 – 2 + 2 = 2
Therefore, F = 2.
(ii). Also, from the statement, we can figure there are 3 components, while the phases are two like the previous one above, i.e. liquid + vapor
F = 3 – 2 + 2 = 5 – 2 = 3
F = 3
(iii). From this statement, we can figure there are 3 components, and the phases are 3 i.e. (2 liquid phases + 1 vapor phase)
From the formula;
F = 3 – 3 + 2 = 0 + 2
F = 2
Answer:
the number of laps in the case when he run for 50 minutes is 18,333.33
Explanation:
The computation of the number of laps in the case when he run for 50 minutes is shown below:
Given that
He runs 440m lap in 1.2 minutes
So in 50 minutes he can have laps of
= 440 × 50 ÷ 1.2
= 18,333.33 laps
hence, the number of laps in the case when he run for 50 minutes is 18,333.33
Answer:
1 mole of a gas would occupy 22.4 Liters at 273 K and 1 atm
Explanation:
An ideal gas is a set of atoms or molecules that move freely without interactions. The pressure exerted by the gas is due to the collisions of the molecules with the walls of the container. The ideal gas behavior is at low pressures, that is, at the limit of zero density. At high pressures the molecules interact and intermolecular forces cause the gas to deviate from ideality.
An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:
P * V = n * R * T
In this case:
- P= 1 atm
- V= 22.4 L
- n= ?
- R= 0.082

- T=273 K
Reemplacing:
1 atm* 22.4 L= n* 0.082
*273 K
Solving:

n= 1 mol
Another way to get the same result is by taking the STP conditions into account.
The STP conditions refer to the standard temperature and pressure. Pressure values at 1 atmosphere and temperature at 0 ° C (or 273 K) are used and are reference values for gases. And in these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.
<u><em>1 mole of a gas would occupy 22.4 Liters at 273 K and 1 atm</em></u>
Answer:
43.0 kJ
Explanation:
The free energy (ΔG) measures the total energy that is presented in a thermodynamic system that is available to produce useful work, especially at thermal machines. In a reaction, the value of the variation of it indicates if the process is spontaneous or nonspontaneous because the free energy intends to decrease, so, if ΔG < 0, the reaction is spontaneous.
The standard value is measured at 25°C, 298 K, and the value of free energy varies with the temperature. It can be calculated by the standard-free energy of formation (G°f), and will be:
ΔG = ∑n*G°f products - ∑n*G°f reactants, where n is the coefficient of the substance in the balanced reaction.
By the balanced reaction given:
2NOCl(g) --> 2NO(g) + Cl2(g)
At ALEKS Data tab:
G°f, NOCl(g) = 66.1 kJ/mol
G°f, NO(g) = 87.6 kJ/mol
G°f, Cl2(g) = 0 kJ/mol
ΔG = 2*87.6 - 2*66.1
ΔG = 43.0 kJ